US4515641A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cleaning control through measurement of electrical conductivity
Assignee: Unilever Patent Holdings BV
•
Filing: 1983-06-21
•
Granted: 1985-05-07
•
Expires: 2003-06-21
Abstract
Abstract There is disclosed a process for cleaning the interior wall of a metal vessel or pipe comprising flooding or turbulently impacting the interior wall of said vessel or pipe with a strongly alkaline or strongly acidic cleaning fluid, simultaneously measuring the conductivity of the cleaning fluid between two electrodes located in the interior of said vessel or pipe and terminating said flooding or impacting when the measured conductivity has been substantially restored to the level measurable with clean electrodes.
Inventors
- 👤 Rudolf Juenger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:14
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/06; G01N27/08; G01N27/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
107 words
A process for cleaning the interior wall of a contaminated metal vessel or pipe comprising flooding or turbulently impacting the interior wall of said vessel or pipe with a strongly alkaline or strongly acidic cleaning fluid, simultaneously measuring the conductivity of the cleaning fluid between two electrodes located in the interior of said vessel or pipe, said electrodes being electrically insulated and separated from each other and with at least one of said electrodes having been subjected to contamination while located in the interior of said vessel or pipe, and terminating said flooding or impacting when the measured conductivity has been substantially restored to a reference level.
Claim 2
Dependent Claim
107 words
A process for cleaning the interior wall of a contaminated metal vessel or pipe comprising flooding or turbulently impacting the interior wall of said vessel or pipe with a strongly alkaline or strongly acidic cleaning fluid, simultaneously measuring the conductivity of the cleaning fluid between two electrodes located in the interior of said vessel or pipe, said electrodes being electrically insulated and separated from each other and with at least one of said electrodes having been subjected to contamination while located in the interior of said vessel or pipe, and terminating said flooding or impacting when the measured conductivity has been substantially restored to a reference level.
Claim 3
Dependent Claim
29 words
The process of claim 1, wherein the cleaning procedure is maintained until at least 90% of a conductivity which had initially been measured with clean electrodes has been reached.
Claim 4
Dependent Claim
29 words
The process of claim 1, wherein the cleaning procedure is maintained until at least 95% of a conductivity which had initially been measured with clean electrodes has been reached.
Claim 5
Dependent Claim
29 words
The process of claim 1, wherein the cleaning procedure is maintained until at least 99% of a conductivity which had initially been measured with clean electrodes has been reached.
Claim 6
Dependent Claim
23 words
The process of claim 1, wherein conductivity values of the cleaning fluid are within a range from 5 to 200 mS·cm -1 .
Claim 7
Dependent Claim
23 words
The process of claim 1, wherein conductivity values of the cleaning fluid are within a range from 5 to 100 mS·cm -1 .
Claim 8
Dependent Claim
23 words
The process of claim 1, wherein conductivity values of the cleaning fluid are within a range from 5 to 80 mS·cm -1 .
Claim 9
Dependent Claim
20 words
The process of claim 1, wherein the temperature of the cleaning fluid is within the range of the operating temperature.
Claim 10
Dependent Claim
23 words
The process of claim 1, wherein the temperature of the cleaning fluid is above the melt temperature of contamination on said interior wall.
Claim 11
Dependent Claim
39 words
The process of claim 1, wherein a metal plate is embedded in an insulated manner in a wall of the vessel or pipe, whereby the metal plate is one said electrode, and said wall is the other said electrode.
References Cited (Backward Citations)
US2183584A
Cited
US2662041A
Cited
US2697673A
Cited
US2909483A
Cited
US3540868A
Cited
US3864083A
Cited
US3910997A
Cited
US3973572A
Cited
DE2542141A1
Cited
US4068162A
Cited
US4375991A
Cited
US4280852A
Cited
US4415859A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-05-06 | 1988-11-05 | 1989-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-06 | 1992-11-05 | 1993-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-06 | 1996-11-05 | 1997-05-07 | $7700.00 | Window Closed / Lapsed |